IEC 61850 DRV relays are provided with a number of software and hardware functions that enable exchanging all the information required by Bus Differential Protection with the Central Bus Differential Protection Unit. Phase current, bus breaker status, and breaker status are retrieved, processed, and transmitted through the DRV to the Central Bus Differential Protection Unit, in order for the latter to process the Bus Differential Protection function algorithms.

Protection Function

Phase overcurrent

Ground overcurrent

Negative sequence overcurrent

Sensitive ground overcurrent

Restrained voltage overcurrent

Directional phase overcurrent

Directional ground overcurrent

Directional sensitive ground overcurrent

Minimum current

Minimum voltage

Maximum voltage

Maximum ground voltage

Negative sequence overvoltage (V Unb.)

Maximum / minimum frequency

Rate of Change

Recloser

Synchronism check

Directional power

Thermal image element

Breaker failure element

Negative sequence overcurrent (I Unb.)

Restrained ground faults

Out-of-step

One overcurrent supervision element per phase of the differential protection trip and the remote end trip via communications.

One overcurrent supervision element per phase of the breaker failure trip.

Dynamic Zone logic element to disable the bay when this has no influence on the differential protection zone.